The prior art is replete with various examples of devices and methods for the removal or “scrubbing” of certain undesirable gaseous components from gas streams in general. One area in which a large number of developments have been made is in the scrubbing of gases produced during oil recovery and storage operations. During such operations, poisonous hydrogen sulfide present presents a health hazard to workmen in the area. To protect the workmen and the public-at-large, the permissible conditions and levels for emissions of hydrogen sulfide are regulated by various regulatory agencies. A few exemplary developments from the prior art follows, each of which are herein incorporated by reference thereto.
U.S. Pat. No. 750,155 teaches a device having a suction producing means and a water tank vertically discharging air through a nozzle below the surface of the water in the tank. There is a sleeve loosely surrounding the nozzle and terminating at its upper end just above the surface of the water, and a cap located a short distance above the upper end of the sleeve.
U.S. Pat. No. 941,676 describes an apparatus for supplying atmospheres of various humidities having: a) an air pump and a means for its operation; b) an air humidifying tank containing water; c) an air tank; d) an exit pipe leading from each tank to the pump; e) a pipe leading from the air tank to beneath the water level of the humidifying tank; and f) a valve mechanism adapted to open communication directly between the air tank and the pump, or indirectly through the humidifying tank.
U.S. Pat. No. 1,018,996 provides a tobacco smoke absorption apparatus having a receptacle for containing liquid, a vertical pipe projecting through the top of the receptacle and having its lower open end terminating adjacent to the bottom of the receptacle, a combustion chamber having an open lower end, and a grating above same, wherein the combustion chamber is mounted on the upper end of the vertical pipe. It further includes a means for causing a downward draft from the combustion chamber and up through the liquid containing receptacle and above it.
U.S. Pat. No. 4,330,510 sets forth a method of scrubbing noxious gas from a gas stream which comprises: a) filling a closed upstanding container having a bottom, a side wall, and a top cover with a gas washing liquid to a predetermined level, the container having a baffle plate mounted substantially horizontally in the container above the predetermined liquid level and being spaced from the side wall of the container about at least substantially the entire periphery of the baffle plate to permit cleansed gas to escape, the space between the baffle plate and the gas washing liquid being substantially unobstructed, the baffle plate having a surface facing the liquid in the lower portion of the container as gas is driven therethrough and to act as an impact wall against which gas-containing bubbles impinge; b) pumping a gas to be processed into at least one drive pipe having an inlet positioned outside of the container and extending into the container with an outlet near the bottom of the container appreciably below the predetermined liquid level to direct the gas stream substantially vertically into the bottom of the container and to form gas-containing bubbles in the gas washing liquid; c) discharging cleansed gas escaping around the periphery of the baffle plate from the container through an outlet stack, the outlet stack communicating with the interior of the container above the baffle plate; and d) impacting the gas-containing bubbles against the baffle plate to cause the gas-containing bubbles to recirculate through the liquid before passing outwardly around the periphery of the baffle plate.
U.S. Pat. No. 4,350,505 discloses a device for treating gases containing nitrogen for utilizing the nitrogen for reduction of oxygen content in well bore drilling fluids and comprising: a) a housing means; b) a chamber provided in the housing means and having a suitable filter material disposed therein to provide a filter chamber; c) a chamber provided in the housing means below the filter chamber and having a suitable liquid disposed therein to provide a liquid bath chamber d) a stand-pipe means disposed in the housing means and providing communication between the filter chamber and the liquid bath chamber; e) a level control means for controlling the level of the liquid bath in the liquid bath chamber; f) a first discharge means in communication with the liquid bath for discharge of the liquid bath; g) a second discharge means in communication with the liquid bath chamber and disposed above the upper level of the liquid bath; h) a means disposed in the liquid bath chamber and disposed above the upper level of the liquid bath to provide a tortuous path of travel between the liquid bath and the second discharge means; i) an inlet means providing access to the interior of the filter chamber for admitting the nitrogen containing gases thereto; and j) a means operably connected with the second discharge means for creating a suction within the housing means for pulling the gases through the filter chamber and liquid bath for removing unwanted debris from the gases and discharging clean gases from the device, including spreader plate means disposed in the filter chamber for dispersing the exhaust gases upon initial entry thereof into the filter chamber.
U.S. Pat. No. 4,511,379 teaches a gas scrubber comprising a first chamber having: a) inner and outer concentric substantially circular side walls each of constant diameter; b) a first end wall extending between corresponding end edges of the side walls; c) a helical second end wall extending between corresponding end edges of the side walls and once therearound to adjacent the first end wall; d) a gas inlet in the outer wall adjacent the position of maximum height thereof, the gas inlet being positioned so as to direct gas passing therethrough tangentially between the side walls; e) a plurality of fluid nozzles disposed on the inner wall so as to spray liquid toward the outer wall; f) gas outlets extending substantially around a side wall and dimensioned so that the velocity of the gas flowing between the walls is substantially constant; and g) liquid outlet means to allow liquid to leave the gas scrubber.
U.S. Pat. No. 4,722,799 describes an apparatus for continuously desulphurizing natural gas and regenerating a reaction solution comprising: a) a contacting means comprised of a tower and solution removal means, the contacting means for contacting natural gas with the reaction solution to substantially oxidize sulphurous compounds in the natural gas; b) a treating means comprised of a collector tank and a recycling means, the recycling means operably connected to the contacting means and the collector tank, the treating means for continuously regenerating the reaction solution, the recycling means for circulating the reaction solution through the contacting means and the treating means; c) a degassing means operably connected to the contacting means and the treating means, the degassing means for removing entrained gases from the reaction solution, wherein the degassing means is comprised of a colloid mill and wherein the recycling means reduces sulphurous compounds in the solution and causes sulphur to precipitate from the solution, the sulphur being removed by a removal mechanism.
U.S. Pat. No. 4,933,118 provides a portable gas scrubbing apparatus comprising: a) oblong casing means for containing a treatment fluid; b) inlet duct means in one end of the casing means for introducing gas into the bottom of the one end of the casing means; c) a first inclined baffle means extending between the sides of the casing means from the one end of the casing means to proximate the other end of the casing means; d) a second inclined baffle means above the first inclined baffle means extending between the sides of the casing means from the other end of the casing means to proximate the one end of the casing means, whereby, when gas is introduced into the casing means to the treatment fluid and the baffle means, the baffles define a circuitous path for gas introduced through the inlet means into the treatment fluid beneath the first baffle means at the one end of the casing means to the top surface of the fluid, thereby ensuring good contact between the gas and the treatment fluid; and outlet duct means in the top of the casing means for discharging treated gas from the casing means. The inlet duct means extends into the casing beneath the first baffle means proximate the one end of the casing means for introducing the gas beneath the first baffle means and horizontal tube means connected to the inlet duct means beneath the first baffle means for distributing the gas beneath the first baffle means.
U.S. Pat. No. 5,064,450 sets forth a gas absorber for removing at least one gaseous component from a flowing gas stream by contacting the gas stream with a lean liquid stream to absorb at least a portion of the gaseous component to produce a rich liquid stream comprising the gaseous component and a flowing gas stream having a reduced concentration of the gaseous component which absorber comprises: a) a double wall forming an annulus having a means for restricting fluid flow into the bottom of the gas absorber from the bottom of the annulus and a means for passing fluid out of an upper section of the annulus into the gas absorber; b) an inlet for the lean liquid stream having a locus in the upper end of the gas absorber; c) an inlet for the flowing gas stream; d) an outlet for the rich liquid stream having a locus in the lower end of the gas absorber; e) an outlet for the flowing gas stream having a reduced concentration of the gaseous component; and f) at least one inlet communicating with the lower end of the annulus which inlet is used to introduce a lean liquid stream at least a portion of which flows upwardly through the annulus and overflows from the top of the annulus and thereby protecting at least a portion of the outer wall from contact with the flowing gas stream.
U.S. Pat. No. 5,102,583 discloses an apparatus for contacting a gas and a liquid comprising: a) a substantially vertical column containing a plurality of substantially horizontal contacting trays is which contacting tray is provided with passages for gas and liquid and wherein at least one of the contacting trays is a control tray; b) a liquid inlet provided in the upper section of the column; c) a gas outlet located above the uppermost contacting tray; d) a gas inlet provided in the lower section of the column; e) a liquid outlet below the lowermost contacting tray; f) a means for controlling the flow of liquid from the control tray; and g) a differential pressure controller responsive to means sensing the density of the mixture of gas and liquid at least one contacting tray above the control tray which controller communicates with the means for controlling the flow of liquid from the control tray and wherein the differential pressure controller is activated by the pressure difference between the space above the uppermost contacting tray and the space below the control tray.
U.S. Pat. No. 5,376,311 teaches an apparatus for mixing gas and liquid comprising: a) a generally rectangular concrete base; b) a vertically extending cylindrical housing mounted on the concrete base and having a hollow interior, and open top end portion and a bottom portion embedded on the concrete base, the bottom portion being provided with horizontal reinforcing bars passing through the walls of the cylindrical housing to anchor the housing with the concrete base, the cylindrical housing being provided with a plurality of apertures disposed at the lower section thereof proximate the concrete base; c) gas diffuser means concentrically held inside the cylindrical housing; the gas diffuser means being defined by an elongated porous tubular member provided with a cap fitted at the top end portion thereof and an elbow fitting detachably secured at the bottom end portion thereof; d) an inlet means consisting of a main pipe having opposite first and second ends, the first end being fitted on the elbow fitting and the second end being connected to a main air supply; and e) a holder means snugly fitted and screwably secured inside the cylindrical housing, the holder means being adapted to hold the porous tubular member in a vertical position as gas from the main supply is distributed therein.
U.S. Pat. No. 5,713,971 describes a cabin air filtration system for removing gas phase contaminants comprising: a) a cavity; b) an air flow path through the cavity; c) a liquid inlet into the cavity; d) a liquid outlet from the cavity; e) a fibrous wicking material having a plurality of elongated strands which are aligned to define a mesh within the cavity, the strands each having a hollow internal region extending longitudinally along the strand connected to an outer surface through at least one slot extending longitudinally along the strand, the hollow internal region transferring liquid from the inlet to the outlet along a path transverse to the air flow path; f) a means for supplying a gas absorbing liquid to the inlet; g) a means for conveying the gas absorbing liquid and any absorbed gases therein from the liquid outlet; and h) a means for circulating air from a cabin, through the mesh along the air flow path, the cavity and back into the cabin, the gas phase contaminants being communicated to the gas absorbing liquid through the slot in the fiber wicking material whereby the gas phase contaminants are absorbed by the gas absorbing liquid retained in the hollow region without essentially affecting the air flow through the mesh.
U.S. Pat. No. 5,730,784 provides a process for the removal of hydrogen sulfide from a gas stream containing hydrogen sulfide, which comprises: a) oxidizing a portion of the hydrogen sulfide therein to form sulfur dioxide therefrom and to produce an oxidized gas stream containing sulfur dioxide and a stoichiometric excess of hydrogen sulfide; b) reacting substantially all the sulfur dioxide in the oxidized gas stream with hydrogen sulfide remaining in the oxidized gas stream in a first liquid phase to form sulfurous material therefrom contained in the first liquid phase and to produce a further gas stream having a decreased and residual hydrogen sulfide content; c) oxidizing substantially all hydrogen sulfide remaining in the further gas stream in a second liquid phase to form a sulfurous material therefrom contained in the second liquid phase and to produce a gas stream substantially free from gaseous sulfur compounds, and d) venting the gas stream substantially free from gaseous sulfur compounds.
U.S. Pat. No. 5,851,389 sets forth a device arranged to be longitudinally inserted and removed from a conduit, and arranged to be positioned at a desired location along the conduit to remove a contaminant from a fluid flowing through the conduit, comprising a container having an axis, the container having: a) a first wall generated about the axis, the first wall being permeable to the fluid stream; b) a second wall generated about the axis, the second wall being spaced from the first wall and being permeable to the fluid stream; c) the first wall defining a first volume; d) the first and second walls defining a second volume therebetween; e) a first member sealing the first and second volumes at one end of the container; f) a second member sealing the second volume at the other end of the container, g) the second volume occupied by filter material; and h) a expandable barrier impervious to the fluid stream positioned adjacent the other end and selectively forming a seal between the second wall and the wall of the conduit. The device may be longitudinally inserted into a conduit and moved to a desired position therealong, and the barrier may be selectively expanded to seal the space between the second wall and the conduit wall, so that the fluid stream flowing through the conduit will be sequentially directed into the first volume, through the first wall, into the second volume where the filter material removes the contaminant from the fluid, and through the second wall.
U.S. Pat. No. 6,004,381 discloses an apparatus for removing gas phase molecules from a fluid stream comprising: a) a plurality of elongated fibers each having a longitudinally extending hollow internal cavity including an opening extending longitudinally along the fiber from the internal cavity to the outer fiber surface; b) a liquid which can absorb the gas phase molecules disposed within the internal cavities of the plurality of elongated fibers; c) a flow path for the fluid stream, containing the gas phase molecules to be removed, directed over a portion of the plurality of elongated fibers whereby the gas phase molecules to be removed are absorbed by the liquid; and d) a means for directing the fluid stream along the flow path.
U.S. Pat. No. 6,506,351 discloses a process for removing nitrogen oxides from a gas stream comprising: a) feeding the gas stream to a nitrogen oxides adsorber selected from the group consisting of a multi-fixed bed adsorber and a rotary wheel adsorber containing a metal oxide based chemisorbent or an adsorbent selected from the group consisting of Y zeolites, gamma alumina, treated gamma alumina, and supported MgO, whereby the nitrogen oxides are adsorbed in the adsorber; and b) feeding an ozone and oxygen containing gas stream to the adsorber, whereby the ozone reacts with the nitrogen oxides to form N2O5.
The prior art includes many more examples of developments directed to similar subject matter. However, none of the prior art devices provide a relatively portable device which is capable of scrubbing gases like hydrogen sulfide from the headspaces of storage tanks or other locations or sources at which the pressure of the gas to be scrubbed exists at a pressure which is only slightly elevated over atmospheric pressure. The present invention provides such apparatus.